Staple cartridge with actuation sled detection

ABSTRACT

A surgical stapling device includes a cartridge assembly having a channel member that defines a cavity and a staple cartridge that is received within the cavity. The staple cartridge includes a cartridge body, pushers, staples, and an actuation sled. The cartridge body includes a proximal portion that has resilient tabs and wall portions that define a proximal portion of the knife slot. The tabs are positioned to engage inner surfaces of the channel member when the staple cartridge is inserted into the cavity. The actuation member includes a guide member that is received within the knife slot and prevents movement of the wall portions from a non-deformed state to a deformed state when the actuation sled is present in the staple cartridge. In the deformed state, passage of a drive assembly into the knife slot is prevented.

FIELD

The disclosure is directed to surgical stapling devices and, more particularly, to surgical stapling devices with staple cartridges that detect the presence of an actuation sled.

BACKGROUND

Surgical stapling devices for simultaneously stapling and cutting tissue are known in the art and are available in a variety of open and endoscopic configurations including linear, circular, and curved. Typically, linear surgical stapling devices that are configured for endoscopic use include a tool assembly that includes a staple cartridge and a knife bar for cutting tissue. The staple cartridge includes a sled that is movable through the staple cartridge to eject staples. In some devices, the sled is positioned to be engaged and advanced through the staple cartridge by the knife bar.

In a process for manufacturing a staple cartridge, multiple checks are provided to confirm the presence of an actuation sled within the staple cartridge of the tool assembly of the stapling device. When an actuation sled is not present in the staple cartridge, advancement of the knife bar through the staple cartridge of the stapling device cuts body tissue but does not eject the staples from the staple cartridge. This may have serious consequences for the patient.

A continuing need exists in the art for a staple cartridge of a tool assembly of a stapling device that can prevent firing of the stapling device when an actuation sled is not present in the staple cartridge.

SUMMARY

Aspects of the disclosure are directed to a surgical stapling device that includes a cartridge assembly that prevents actuation of the stapling device when an actuation sled is not present in the stapling device. The cartridge assembly has a channel member that defines a cavity and a staple cartridge that is received within the cavity. The staple cartridge includes a cartridge body, pushers, staples, and an actuation sled. The cartridge body defines a knife slot and staple receiving pockets positioned on each side of the knife slot and includes a proximal portion that has resilient tabs and wall portions that define a proximal portion of the knife slot. The tabs are positioned to engage inner surfaces of the channel member when the staple cartridge is inserted into the cavity to urge the wall portions from a non-deformed state to a deformed state to reduce a width of the knife slot. The actuation member includes a guide member that is received within the knife slot and prevents movement of the wall portions from the non-deformed state to the deformed state when the actuation sled is present in the staple cartridge. In the deformed state, passage of a drive assembly into the knife slot is prevented.

Aspects of the disclosure are directed to a tool assembly including an anvil assembly, a cartridge assembly, and a drive assembly. The cartridge assembly is coupled to the anvil assembly and is movable in relation to the anvil assembly between open and clamped positions. The cartridge assembly includes a channel member, and a staple cartridge. The channel member has side walls and a bottom wall that define a cavity. Each of the side walls of the channel member has an inner surface. The staple cartridge includes a cartridge body having side walls, pushers, staples, and an actuation sled. The cartridge body defines a knife slot having a width and staple receiving pockets positioned on each side of the knife slot. Each of the staple receiving pockets receives one of the pushers and one of the staples which is supported on the pusher. The actuation sled includes a guide member and cam members positioned on each side of the guide member. The guide member is received within the knife slot. The cartridge body includes a proximal portion that has resilient tabs and wall portions that define a proximal portion of the knife slot. The resilient tabs extend outwardly of the side walls of the cartridge body and are positioned to engage the inner surfaces of the side walls of the channel member when the staple cartridge is inserted into the cavity of the channel member. The wall portions are deflectable inwardly from a non-deformed state to a deformed state to change the width of the proximal portion of the knife slot. Insertion of the staple cartridge into the cavity of the channel member causes the resilient tabs to move inwardly to move the wall portions from the non-deformed state towards the deformed state. The drive assembly includes a flexible beam and an I-beam. The flexible beam has a proximal portion and a distal portion. The I-beam is coupled to the distal portion of the flexible beam and includes an upper beam, a lower beam, and a vertical strut. The vertical strut has a width that facilitates passage of the vertical strut into the knife slot when the wall portions are in the non-deformed state but prevents passage of the vertical strut into the knife slot when the wall portions are in the deformed state.

Other aspects of the disclosure are directed to a cartridge assembly that includes a channel member and a staple cartridge. The channel member has side walls and a bottom wall that define a cavity. Each of the side walls of the channel member has an inner surface. The staple cartridge includes a cartridge body having side walls, pushers, staples, and an actuation sled. The cartridge body defines a knife slot having a width and staple receiving pockets positioned on each side of the knife slot. Each of the staple receiving pockets receives one of the pushers and one of the staples which is supported on the pusher. The actuation sled includes a guide member and cam members positioned on each side of the guide member. The guide member is received within the knife slot. The cartridge body includes a proximal portion that has resilient tabs and wall portions that define a proximal portion of the knife slot. The resilient tabs extend outwardly of the side walls of the cartridge body and are positioned to engage the inner surfaces of the side walls of the channel member when the staple cartridge is inserted into the cavity of the channel member. The wall portions are deflectable inwardly from a non-deformed state to a deformed state to change the width of the proximal portion of the knife slot. Insertion of the staple cartridge into the cavity of the channel member causes the resilient tabs to move inwardly to move the wall portions from the non-deformed state towards the deformed state. The drive assembly includes a flexible beam and an I-beam. The flexible beam has a proximal portion and a distal portion. The I-beam is coupled to the distal portion of the flexible beam and includes an upper beam, a lower beam, and a vertical strut. The vertical strut has a width that facilitates passage of the vertical strut into the knife slot when the wall portions are in the non-deformed state but prevents passage of the vertical strut into the knife slot when the wall portions are in the deformed state.

In aspects of the disclosure, the guide member of the actuation sled prevents movement of the wall portions from the non-deformed state to the deformed state when the guide member is positioned within the knife slot.

In some aspects of the disclosure, the proximal portion of the cartridge body defines a cutout that is positioned adjacent to each of the tabs, and the tabs are deformed into the cutouts when the staple cartridge is inserted into the cavity of the channel member.

In certain aspects of the disclosure, inward deformation of the tabs urges the wall portions towards the deformed state.

In aspects of the disclosure, the staple cartridge is releasably supported within the cavity of the channel member.

In some aspects of the disclosure, the cartridge body of the staple cartridge defines three rows of the staple receiving pockets on each side of the knife slot.

Other aspects of the disclosure are directed to a surgical stapling device including an elongate body and a tool assembly. The elongate body has a proximal portion and a distal portion. The tool assembly is supported on the distal portion of the elongate body and includes an anvil assembly, a cartridge assembly, and a drive assembly. The cartridge assembly is coupled to the anvil assembly and is movable in relation to the anvil assembly between open and clamped positions. The cartridge assembly includes a channel member, and a staple cartridge. The channel member has side walls and a bottom wall that define a cavity. Each of the side walls of the channel member has an inner surface. The staple cartridge includes a cartridge body having side walls, pushers, staples, and an actuation sled. The cartridge body defines a knife slot having a width and staple receiving pockets positioned on each side of the knife slot. Each of the staple receiving pockets receives one of the pushers and one of the staples which is supported on the pusher. The actuation sled includes a guide member and cam members positioned on each side of the guide member. The guide member is received within the knife slot. The cartridge body includes a proximal portion that has resilient tabs and wall portions that define a proximal portion of the knife slot. The resilient tabs extend outwardly of the side walls of the cartridge body and are positioned to engage the inner surfaces of the side walls of the channel member when the staple cartridge is inserted into the cavity of the channel member. The wall portions are deflectable inwardly from a non-deformed state to a deformed state to change the width of the proximal portion of the knife slot. Insertion of the staple cartridge into the cavity of the channel member causes the resilient tabs to move inwardly to move the wall portions from the non-deformed state towards the deformed state. The drive assembly includes a flexible beam and an I-beam. The flexible beam has a proximal portion and a distal portion. The I-beam is coupled to the distal portion of the flexible beam and includes an upper beam, a lower beam, and a vertical strut. The vertical strut has a width that facilitates passage of the vertical strut into the knife slot when the wall portions are in the non-deformed state but prevents passage of the vertical strut into the knife slot when the wall portions are in the deformed state.

In aspects of the disclosure, the handle assembly is coupled to the proximal portion of the elongate body.

Other features of the disclosure will be appreciated from the following description.

DESCRIPTION OF THE DRAWINGS

Various aspects of the disclosure are described herein below with reference to the drawings, wherein:

FIG. 1 is a side perspective view of a surgical stapling device including a staple cartridge according to aspects of the disclosure;

FIG. 2 is an enlarged view of the indicated area of detail shown in FIG. 1 illustrating a tool assembly of the surgical stapling device shown in FIG. 1 ;

FIG. 3 is a side perspective view of a cartridge assembly of the tool assembly shown in FIG. 2 including a staple cartridge having an actuation sled;

FIG. 4 is an exploded view of the cartridge assembly shown in FIG. 3 ;

FIG. 5 is an enlarged view of the indicated area of detail shown in FIG. 4 illustrating a proximal portion of the staple cartridge;

FIG. 6 is an enlarged view of the indicated area of detail shown in FIG. 3 illustrating a proximal portion of the cartridge assembly including a staple cartridge having an actuation sled;

FIG. 6A is an enlarged view of the proximal portion of the cartridge assembly shown in FIG. 3 including with an actuation sled present in the staple cartridge;

FIG. 7 is a cross-sectional view taken along section line 7-7 of FIG. 5 illustrating a proximal portion of the cartridge assembly of the surgical stapling device of the tool assembly shown in FIG. 3 with an actuation sled present in the staple cartridge;

FIG. 8 is a cross-sectional view taken along section line 8-8 of FIG. 2 illustrating the proximal portion of the tool assembly shown in FIG. 2 with an actuation sled present in the staple cartridge;

FIG. 9 is a top, partial cross-sectional view of the proximal portion of the cartridge assembly shown in FIG. 8 with the actuation sled present in the staple cartridge;

FIG. 10 is a cross-sectional view taken through the proximal portion of the tool assembly illustrating with a staple cartridge that does not include an actuation sled; and

FIG. 11 is a cross-sectional view taken along section line 11-11 of FIG. 10 .

DETAILED DESCRIPTION

The disclosed surgical stapling device will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. However, it is to be understood that the aspects of the disclosure described herein are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure. In addition, directional terms such as front, rear, upper, lower, top, bottom, distal, proximal, and similar terms are used to assist in understanding the description and are not intended to limit the disclosure.

In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician during use of the device in its customary manner, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician during use of the device in its customary manner. In addition, the term “endoscopic” is used generally used to refer to endoscopic, laparoscopic, arthroscopic, and/or any other procedure conducted through small diameter incision or cannula. Further, the term “clinician” is used generally to refer to medical personnel including doctors, nurses, and support personnel. Moreover, directional terms such as front, rear, upper, lower, top, bottom, and similar terms are used to assist in understanding the description and are not intended to limit the disclosure.

The disclosure is directed to a surgical stapling device that includes a cartridge assembly that prevents actuation of the stapling device when an actuation sled is not present in the stapling device. The cartridge assembly has a channel member that defines a cavity and a staple cartridge that is received within the cavity. The staple cartridge includes a cartridge body, pushers, staples, and an actuation sled. The cartridge body defines a knife slot and staple receiving pockets positioned on each side of the knife slot and includes a proximal portion that has resilient tabs and wall portions that define a proximal portion of the knife slot. The tabs are positioned to engage inner surfaces of the channel member when the staple cartridge is inserted into the cavity to urge the wall portions from a non-deformed state to a deformed state to reduce a width of the knife slot. The actuation member includes a guide member that is received within the knife slot and prevents movement of the wall portions from the non-deformed state to the deformed state when the actuation sled is present in the staple cartridge. In the deformed state, passage of a drive assembly into the knife slot is prevented.

FIG. 1 illustrates exemplary aspects of the disclosed surgical stapling device shown generally as stapling device 10. The stapling device 10 includes a handle assembly 12, an elongate body 14 defining a longitudinal axis “X” (FIG. 1 ), and a tool assembly 16. The handle assembly 12 includes a stationary handle 18 and a trigger 20 that is movable in relation to the stationary handle 18 to actuate the tool assembly 16. In aspects of the disclosure, the stapling device 10 includes a rotation knob 22 and an articulation lever 24. The rotation knob 22 is rotatably coupled to a distal portion of the handle assembly 12 and supports the elongate body 14 to facilitate rotation of the elongate body 14 and the tool assembly 16 in relation to the handle assembly 12 about the longitudinal axis “X”. The articulation lever 24 is coupled to the tool assembly 16 to articulate the tool assembly 16 about an axis “Z” that is transverse to the longitudinal axis “X” from a position aligned with the longitudinal axis “X” to positions defining acute angles with the longitudinal axis “X”. In some aspects of the stapling device 10, the handle assembly 12 includes retraction knobs 26 for retracting a drive assembly (not shown) of the stapling device 10. For a more detailed description of exemplary aspects of the handle assembly 12 of the stapling device 10, see, e.g., U.S. Pat. No. 6,241,139. Although the handle assembly 12 is illustrated as a manually operated handle assembly, it is envisioned that the handle assembly 12 could be a powered handle assembly such as described in U.S. Pat. No. 9,055,943. It is also envisioned that the tool assembly 16 described herein could be incorporated into a robotic surgical system.

FIG. 2 illustrates the tool assembly 16 of the stapling device 10 (FIG. 1 ). The tool assembly 16 includes an anvil assembly 28 and a cartridge assembly 30 that are movable in relation to each other between an open position (FIG. 2 ) in which the anvil assembly 28 and the cartridge assembly 30 are spaced from each other and a clamped position in which the anvil assembly 28 and the cartridge assembly 30 are in juxtaposed alignment. In aspects of the disclosure, the anvil assembly 28 and the cartridge assembly 30 are coupled together with pivot members (not shown) that facilitate pivotable movement of the cartridge assembly 32 in relation to the anvil assembly 28 between the open and clamped positions. Although the cartridge assembly 30 is illustrated as pivoting towards a stationary anvil assembly 28, it is envisioned that the anvil assembly 28 could be adapted to pivot towards a stationary cartridge assembly 30.

FIGS. 3 and 4 illustrate the cartridge assembly 30 which includes a channel member 32 and a staple cartridge 34. The channel member 32 includes side walls 32 a and a bottom wall 32 b that define a cavity 36 (FIG. 9 ) that receives the staple cartridge 34. The staple cartridge 34 can be configured to be fixedly received in the cavity 36 of the channel member 32. Alternately, the staple cartridge 34 can be configured to be releasably supported within the cavity 36 of the channel member 32 such that the staple cartridge 34 can be replaced after each firing to facilitate reuse of the stapling device 10 (FIG. 1 ).

The staple cartridge 34 includes a cartridge body 38, pushers 40, staples 42, and an actuation sled 44. The cartridge body 38 defines a knife slot 46 and staple receiving pockets 48 that are positioned on opposite sides of the knife slot 46. In aspects of the disclosure, the knife slot 48 is centrally located along a longitudinal axis of the staple cartridge 34 and extends from a proximal end of the cartridge body 38 towards the distal end of the cartridge body 38. In some aspects of the disclosure, the staple receiving pockets 48 are aligned in rows, e.g., three rows, on each side of the knife slot 48. Each of the staple receiving pockets 48 receives a pusher 40 and a staple 42 with the staple 42 being supported on the pusher 40 within the staple receiving pocket 48. The knife slot 46 and the staple receiving pockets 48 extend through a tissue engaging surface 50 of the cartridge body 38.

The actuation sled 44 is received within the cartridge body 38 and is movable from a retracted position to an advanced position to eject the staples 42 from the staple receiving pockets 48 of the cartridge body 38. More specifically, the actuation sled 44 includes a guide member 52 and cam members 54 that are positioned on opposite sides of the guide member 52. In aspects of the disclosure, the guide member 52 is centrally located on the actuation sled 44. Each of the cam members 54 includes an angled distal surface that is aligned with the pushers 40 such that movement of the actuation sled 44 from its retracted position to its advanced position lifts the pushers 40 within the staple receiving pockets 48 to eject the staples 42 from the cartridge body 38. The central guide member 52 has a width that is substantially equal to the width of the knife slot 46 and is received within the knife slot 46 when the cartridge body 38 is in an unbiased state. When the actuation sled 44 moves from its retracted position towards its advanced position, the guide member 52 moves through the knife slot 46.

The cartridge body 38 includes a proximal portion 60 which is illustrated in FIGS. 5 and 6 and includes resilient tabs 62 that extend outwardly of side walls 64 of the cartridge body 38 and define a width (between the outer surfaces of the resilient tabs 62) that is greater than the width of the cavity 36 of the channel member 32. Each of the tabs 62 is aligned with a respective cutout 66 formed in the proximal portion 60 of the cartridge body 38. When the staple cartridge 34 is received within the cavity 36 of the channel member 32, the resilient tabs 62 press against inner surfaces of the side walls 32 a of the channel member 32 to urge wall portions 70 (FIG. 6 ) of the cartridge body 38 defining a proximal portion of the knife slot 46 inwardly towards each other to narrow the width of the knife slot 46. If an actuation sled 44 is received in the cartridge body 38 (FIG. 6 ), the central guide member 52 of the actuation sled 44 is received in the knife slot 46 and prevents inward movement of the wall portions 70 of the cartridge body 38 when the staple cartridge 34 is inserted into the cavity 36 of the channel member 32 to prevent narrowing of the knife slot 46. If an actuation sled 44 is not present within the staple cartridge 34 (FIG. 6A), insertion of the staple cartridge 34 into the cavity 36 of the channel member 32 causes the tabs 62 to engage the inner surfaces of the side walls 32 a of the channel member 32 to urge the wall portions 70 of the cartridge body 38 inwardly to narrow the knife slot 46.

The tool assembly 16 of the stapling device 10 (FIG. 1 ) includes a drive assembly 80 illustrated in FIG. 4 . The drive assembly 80 includes a flexible beam 82 and an I-beam 84. The flexible beam 82 has a proximal portion 86 and a distal portion 88. The proximal portion 86 of the flexible beam 82 is adapted to be coupled to a drive shaft (not shown) that is supported within the elongate body 14 of the stapling device 10, and the distal portion 88 of the flexible beam 82 is secured to the I-beam 84. In aspects of the disclosure, the distal portion 88 of the flexible beam 82 is welded to the I-beam 84. Alternately, the flexible beam 82 can be coupled to the I-beam 84 using a variety of different fastening techniques, e.g., interlocking structure, rivets, or the like.

The I-beam 84 includes an upper beam 90, a lower beam 92, and a vertical strut 94 that secures the upper and lower beams 90, 92 together. The vertical strut 94 is aligned with knife slot 46 and includes a distal face that defines a cutting edge 96. The I-beam 94 is positioned proximally of the staple cartridge 34 when the stapling device 10 (FIG. 1 ) is in an open position. When the firing trigger 20 (FIG. 1 ) is actuated, i.e., pressed towards the stationary handle 18, the drive assembly 80 is moved from a retracted position towards an advanced position. As the drive assembly 80 begins to move towards the advanced position, the vertical strut 94 moves into the knife slot 46 of the cartridge body 38, the upper beam 90 engages the anvil assembly 28, and the lower beam 92 engages the channel member 32 of the cartridge assembly 30 to move the tool assembly 16 (FIG. 1 ) from the open position to the clamped position. Upon continued advancement of the drive assembly 80, the vertical strut 94 of the I-beam 84 engages the actuation sled 44 and advances the actuation sled 44 through the cartridge body 38 of the staple cartridge 34. As the actuation sled 44 moves through the cartridge body 38, the cam members 54 of the actuation sled 44 sequentially engage the pushers 40 to sequentially eject the staples 42 from the staple receiving pockets 48 of the cartridge body 38. As the I-beam 84 moves through the cartridge body 38 of the staple cartridge 34, the cutting edge 96 of the I-beam 84 cuts tissue clamped between the anvil assembly 28 and the cartridge assembly 30.

FIGS. 7-9 illustrate a tool assembly 16 that includes a staple cartridge 34 having an actuation sled 44. The width of the vertical strut 94 is substantially equal to the width of the knife slot 46 when the wall portions 70 of the cartridge body 38 are in an unbiased state. When an actuation sled 44 is present in the staple cartridge 34, the guide member 52 of the actuation sled is received within the knife slot 46 to prevent inward movement of the wall portions 70 of the cartridge body 38 defining the knife slot 46 when the staple cartridge 34 is inserted into the channel member 32 of the cartridge assembly 30. Thus, when the stapling device 10 is fired, the vertical strut 94 of the I-beam 84 can move into and through the knife slot 46 to actuate the tool assembly 16.

FIGS. 10 and 11 illustrate a tool assembly 16 that includes a staple cartridge 34 in which an actuation sled 44 is not present. When an actuation sled 44 is not present in the staple cartridge 34, the tabs 62 on the proximal portion 60 of the cartridge body 38 engage the inner surfaces of the side walls 32 a of the channel member 32 as the staple cartridge 34 is inserted into the cavity 36 of the channel member 36 to urge the wall portions 70 of the cartridge body 38 defining the knife slot 46 inwardly in the direction of arrows “A” in FIG. 10 to narrow the width of the knife slot 46. In the narrowed state of the knife slot 46, the width of the vertical strut 94 of the I-beam 84 is greater than the width of the knife slot 46. As such, the I-beam 84 of the drive assembly 80 is prevented from moving into the knife slot 46 of the cartridge body 38 of the staple cartridge 34 to prevent actuation of the tool assembly 16 (FIG. 1 ).

The cartridge assembly 30 prevents actuation of the tool assembly 16 when an actuation sled 44 is not present in the staple cartridge 34 to prevent the tool assembly 16 from cutting tissue when staples 40 cannot be ejected from the staple cartridge 34.

Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary aspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with one exemplary aspect of the disclosure may be combined with the elements and features of another without departing from the scope of the disclosure. As well, one skilled in the art will appreciate further features and advantages of the disclosure based on the above-described aspects of the disclosure. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. 

What is claimed is:
 1. A tool assembly comprising: an anvil assembly; a cartridge assembly coupled to the anvil assembly, the cartridge assembly being movable in relation to the anvil assembly between open and clamped positions, the cartridge assembly including: a channel member having side walls and a bottom wall that define a cavity, each of the side walls having an inner surface; and a staple cartridge including a cartridge body having side walls, pushers, staples, and an actuation sled, the cartridge body defining a knife slot having a width and staple receiving pockets positioned on each side of the knife slot, each of the staple receiving pockets receiving one of the pushers and one of the staples supported on the pusher, the actuation sled including a guide member and cam members positioned on each side of the guide member, the guide member received within the knife slot, the cartridge body including a proximal portion having resilient tabs and wall portions that define a proximal portion of the knife slot, the resilient tabs extending outwardly of the side walls of the cartridge body and positioned to engage the inner surfaces of the side walls of the channel member when the staple cartridge is inserted into the cavity of the channel member, the wall portions being deflectable inwardly from a non-deformed state to a deformed state to change the width of the proximal portion of the knife slot, wherein insertion of the staple cartridge into the cavity of the channel member causes the resilient tabs to urge the wall portions from the non-deformed state towards the deformed state; and a drive assembly including a flexible beam and an I-beam, the flexible beam having a proximal portion and a distal portion, the I-beam coupled to the distal portion of the flexible beam and including an upper beam, a lower beam, and a vertical strut, the vertical strut having a width that facilitates passage of the vertical strut into the knife slot when the wall portions are in the non-deformed state but prevents passage of the vertical strut into the knife slot when the wall portions are in the deformed state.
 2. The tool assembly of claim 1, wherein the guide member of the actuation sled prevents movement of the wall portions from the non-deformed state to the deformed state when the guide member is positioned within the knife slot.
 3. The tool assembly of claim 1, wherein the proximal portion of the cartridge body defines a cutout positioned adjacent to each of the tabs, the tabs being deformed into the cutouts when the staple cartridge is inserted into the cavity of the channel member.
 4. The tool assembly of claim 3, wherein inward deformation of the tabs urges the wall portions towards the deformed state.
 5. The tool assembly of claim 1, wherein the staple cartridge is releasably supported within the cavity of the channel member.
 6. The tool assembly of claim 1, wherein the cartridge body of the staple cartridge defines three rows of the staple receiving pockets on each side of the knife slot.
 7. A surgical stapling device comprising: an elongate body having a proximal portion and a distal portion; and a tool assembly supported on the distal portion of the elongate body, the tool assembly including: an anvil assembly; a cartridge assembly coupled to the anvil assembly, the cartridge assembly being movable in relation to the anvil assembly between open and clamped positions, the cartridge assembly including: a channel member having side walls and a bottom wall that define a cavity, each of the side walls having an inner surface; and a staple cartridge including a cartridge body having side walls, pushers, staples, and an actuation sled, the cartridge body defining a knife slot having a width and staple receiving pockets positioned on each side of the knife slot, each of the staple receiving pockets receiving one of the pushers and one of the staples supported on the pusher, the actuation sled including a guide member and cam members positioned on each side of the guide member, the guide member received within the knife slot, the cartridge body including a proximal portion having resilient tabs and wall portions that define a proximal portion of the knife slot, the resilient tabs extending outwardly of the side walls of the cartridge body and positioned to engage the inner surfaces of the side walls of the channel member when the staple cartridge is inserted into the cavity of the channel member, the wall portions being deflectable inwardly from a non-deformed state to a deformed state to change the width of the proximal portion of the knife slot, wherein insertion of the staple cartridge into the cavity of the channel member causes the resilient tabs to urge the wall portions from the non-deformed state towards the deformed state; and a drive assembly including a flexible beam and an I-beam, the flexible beam having a proximal portion and a distal portion, the I-beam coupled to the distal portion of the flexible beam and including an upper beam, a lower beam, and a vertical strut, the vertical strut having a width that facilitates passage of the vertical strut into the knife slot when the wall portions are in the non-deformed state but prevents passage of the vertical strut into the knife slot when the wall portions are in the deformed state.
 8. The surgical stapling device of claim 7, wherein the guide member of the actuation sled prevents movement of the wall portions from the non-deformed state to the deformed state when the guide member is positioned within the knife slot.
 9. The surgical stapling device of claim 7, wherein the proximal portion of the cartridge body defines a cutout positioned adjacent to each of the tabs, the tabs being deformed into the cutouts when the staple cartridge is inserted into the cavity of the channel member.
 10. The surgical stapling device of claim 9, wherein inward deformation of the tabs urges the wall portions towards the deformed state.
 11. The surgical stapling device of claim 7, wherein the staple cartridge is releasably supported within the cavity of the channel member.
 12. The surgical stapling device of claim 7, wherein the cartridge body of the staple cartridge defines three rows of the staple receiving pockets on each side of the knife slot.
 13. The surgical stapling device of claim 7, further including a handle assembly coupled to the proximal portion of the elongate body.
 14. A cartridge assembly comprising: a channel member having side walls and a bottom wall that define a cavity, each of the side walls having an inner surface; and a staple cartridge including a cartridge body having side walls, pushers, staples, and an actuation sled, the cartridge body defining a knife slot having a width and staple receiving pockets positioned on each side of the knife slot, each of the staple receiving pockets receiving one of the pushers and one of the staples supported on the pusher, the actuation sled including a guide member and cam members positioned on each side of the guide member, the guide member received within the knife slot, the cartridge body including a proximal portion having resilient tabs and wall portions that define a proximal portion of the knife slot, the resilient tabs extending outwardly of the side walls of the cartridge body and positioned to engage the inner surfaces of the side walls of the channel member when the staple cartridge is inserted into the cavity of the channel member, the wall portions being deflectable inwardly from a non-deformed state to a deformed state to change the width of the proximal portion of the knife slot, wherein insertion of the staple cartridge into the cavity of the channel member causes the resilient tabs to urge the wall portions from the non-deformed state towards the deformed state.
 15. The cartridge assembly of claim 14, wherein the guide member of the actuation sled prevents movement of the wall portions from the non-deformed state to the deformed state when the guide member is positioned within the knife slot.
 16. The cartridge assembly of claim 14, wherein the proximal portion of the cartridge body defines a cutout positioned adjacent to each of the tabs, the tabs being deformed into the cutouts when the staple cartridge is inserted into the cavity of the channel member.
 17. The cartridge assembly of claim 16, wherein inward deformation of the tabs urges the wall portions towards the deformed state.
 18. The cartridge assembly of claim 14, wherein the staple cartridge is releasably supported within the cavity of the channel member.
 19. The cartridge assembly of claim 14, wherein the cartridge body of the staple cartridge defines three rows of the staple receiving pockets on each side of the knife slot. 